Camera skater dolly, rail and clamp system

ABSTRACT

A track system on which a skater dolly can roll, comprising one or more pairs of rails and one or more rail clamps. Each rail clamp supports one or two pairs of rails. Rails held side-by-side are parallel to each other. Rail clamps can also secure two rails in end-to-end configuration. The distance between rails can be about 5/16 of an inch. The track system can include a skater dolly, the load-bearing wheels of which are angled 20-30 degrees away from vertical to provide clearance past the rail clamps. The skater also has stabilizing wheels that are approximately perpendicular to the load-bearing wheels, and which secure the skater to the rails when the skater is in a non-upright e.g. upside-down orientation. The system can include a motor pulley system that moves the skater along the rails.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Ser. No. 62/323,600, filed onApr. 15, 2016, the contents of which are hereby incorporated byreference in their entirety.

TECHNICAL FIELD

The present invention relates generally to moveable dolly systems forcameras, in which the dolly is mounted on a track or rail assembly suchas a pair of rails. The invention provides a skater dolly, rail andclamp system for such movement.

BACKGROUND ART

Skater (or “slider”) dolly systems provide a means for moving a cameraor other equipment smoothly along a predetermined path. They are widelyused in the movie industry. They comprise parallel rails on which askater dolly is mounted. The parallel rails must somehow be secured inposition in relation to each other. This may be accomplished by a tie orcoupler that is attached to each rail. The skater typically compriseswheels on which the skater rolls along the rails. The skater alsocomprises a platform to which a tripod or other equipment support isattached or mounted. A camera or other equipment is mounted on thetripod or other support. Current skater dolly systems are difficult touse for various reasons, including that it is cumbersome and difficultto assemble the rails; rails and couplers are typically costly; therail-to-rail distance typically ranges from about 8 inches to about 24inches, which limits the usefulness of rails in confined spaces; fewsystems provide for the use of a motorized dolly; rail length is subjectto specific limits, consequently limiting flexibility with respect tothe distance a camera can travel; couplers typically are limited in thatthey can only be used in the rail system they were designed for.

There remains a need for a more versatile and easy-to-use system thatcomprises a skater dolly, rail and clamp, wherein the system can be usedin confined spaces, provides easy portability, and provides greater easeof assembly and use than current systems. At the same time, a system isdesirable that possesses a low profile and small size so that, forexample, the image captured by a camera mounted on the dolly includeslittle or none of the equipment itself. The inventive system describedherein provides these and other advantages.

SUMMARY OF INVENTION

The present invention provides, in one embodiment, a camera skater dolly(also referred to herein as a skater, slider dolly, and slider), railand clamp system. In an embodiment, the system comprises threecomponents: a skater dolly, two rails (the terms “rail” and “pipe” areused interchangeably throughout the specification), and one or moreclamps. See FIGS. 1-5C. The clamps function to hold the rails parallelto each other and a prescribed distance apart from each other. A notableaspect of the invention is that the prescribed distance between rails isvery short, in the range of from about one-quarter inch (¼″) to 3 inches(3″), such as 5/16 inches, one-half inch (½), one inch (1″), or one andone-half inches (1½″). Also notably, the clamps can simultaneously beused to hold side-by-side rails parallel to each other and to join railsin series, in line in and end-to-end linear configuration. A combinationof clamps and pipes thus can provide a set of rails in a great varietyof lengths, depending on the user's needs. The clamps comprise a top andbottom plate joined by a screw. The pipes are positioned between the topand bottom plate and the screw is tightened, thus pressing the top andbottom plates against the pipes. In an embodiment, the top plate isconfigured and positioned such that it makes one contact with each pipe,while the bottom plate is configured and positioned such that it makestwo contacts with each pipe. The clamp thus can offer the advantage ofsimple assembly with a single screw while securely holding the pipes.

The skater dolly can resemble a standard wheeled dolly as known and usedin the art, modified to include an angled set of four top wheels, and aset of four side (also referred to as “stabilizing”) wheels. The topwheels function as load-bearing wheels when the dolly is in uprightposition and, in an embodiment, are larger than the four stabilizingwheels. A novel aspect of the invention is that the four top wheels areangled away from vertical so that their path is not impeded by the topplate of the clamp. While the load-bearing wheels make contact with thetop or upper half of the rail, the four side wheels make contact withthe bottom or lower half of the rail. The smaller wheels secure theskater to the rails such that the skater remains on the rails in anyorientation between and including right-side-up and upside-down, such assideways (one rail above the other).

In another embodiment, the system comprises, as described above, askater dolly, two rails, and one or more clamps, and further comprises amotor mounted on the skater, the motor being attached to a pulley, andfurther comprises a belt secured next to and parallel to the rails, suchthat the motor functions to provide hands-free propulsion of the skateralong the rails. See FIGS. 6-10. The non-motorized and motorizedembodiments each may further include a camera mounted on the skaterdolly directly or via a tripod or other mounting system, such as thefour-legged high-hat described in U.S. Patent Application Publication2015/0226371 (“equipment mounting module,” see, e.g., '371 publicationat FIG. 6E).

In another embodiment, the system comprises two rails and one or moreclamps, as described above. See FIGS. 11-12.

The invention further provides a track system on which a skater dollycan roll, comprising one or more pairs of side-by-side rails and one ormore rail clamps, wherein at least one rail clamp comprises a clamp top,a clamp bottom and a clamp screw that joins the clamp top to the clampbottom, and said at least one rail clamp secures in place at least onepair of rails, and holds each member of each secured pair parallel tothe other member of the pair, the distance between rails is betweenabout 5/16 inches and about 3 inches, the clamp top comprises two angledlower surfaces, each of which makes contact with one of the rails, andthe clamp bottom comprises two depressions, each of which supports onerail.

In an embodiment of such a system, each depression of the clamp bottomis formed by three flat faces angled such that one face is horizontaland the other two are non-horizontal, and each non-horizontal face makescontact with the rail that the corresponding depression supports whilethe horizontal face does not make such contact. In a preferredembodiment, the distance between rails is about 5/16 inches. In anotherembodiment, such a system further comprises a skater dolly, wherein theskater dolly comprises a set of four load-bearing wheels and a set offour stabilizing wheels, wherein the load-bearing wheels are angled20-30 degrees away from vertical and the stabilizing wheels are aboutperpendicular to the load-bearing wheels. Such a system may furthercomprise a motor pulley system that moves the skater along the rails,wherein the motor pulley system comprises a motor assembly mounted onthe skater, a belt, and idler pulleys.

Other objects and features of the present invention will become apparentfrom the following detailed description considered in conjunction withthe accompanying drawings. It is to be understood, however, that thedrawings are designed solely for purposes of illustration and not as adefinition of the limits of the invention, for which reference should bemade to the appended claims.

BRIEF DESCRIPTION OF DRAWINGS

In the drawings, wherein like reference characters denote correspondingor similar elements throughout the various figures:

FIG. 1 is an isometric view of an embodiment of the system 1 (notmotorized), showing back and front rails 10, left and right rail clamps12 holding the rails in place, and the skater dolly 14 with carriageplate 20 and flat mounting plate 22.

FIG. 2 is an exploded view of the skater dolly 14 with carriage plate 20and flat mounting plate 22 of the system 1 shown in FIG. 1.

FIG. 3 is a front view of the embodiment of the system 1 shown in FIG.1.

FIG. 4 is a top view of the embodiment of the system 1 shown in FIG. 1.

FIG. 5A is an enlarged side view of the system 1 shown in FIG. 1.

FIG. 5B is an enlarged side view of the system 1 shown in FIG. 1,rotated 90 degrees.

FIG. 5C is an enlarged side view of the system 1 shown in FIG. 1,rotated 180 degrees.

FIG. 6 is an isometric view of an embodiment of the system 2(motorized), substantially the same as the system 1 of FIG. 1 exceptfurther comprising a motor assembly 60 mounted on the skater 14 and abelt 62 running the length of the rails, along which the motor assembly60 pulls the skater 14.

FIG. 7 is a partially exploded view of the embodiment of the system 2shown in FIG. 6.

FIG. 8 is a front view of the embodiment of the system 2 shown in FIG.6.

FIG. 9 is a top view of the embodiment of the system 2 shown in FIG. 6.

FIG. 10 is an enlarged side view of the system 2 shown in FIG. 6.

FIG. 11 is an exploded view of an embodiment of a system 3 comprisingrails 10 and a rail clamp 12 that secures the rails, the clampcomprising the clamp top 16 joined by a clamp screw 46 to the clampbottom 18.

FIG. 12 is an enlarged side view of the embodiment shown in FIG. 11.

FIG. 13 shows an embodiment in which the rail clamp 12 holds rails 10 aand 10 b end-to-end while at the same time securing rails 10 a and 10 aside-by-side and rails 10 b and 10 b side-by-side.

DETAILED DESCRIPTION OF EMBODIMENTS

Referring now to FIG. 1, the invention provides, in one embodiment, asystem 1 that comprises a camera skater dolly 14, two parallel rails 10and one or more rail clamps 12. The rail clamps 12 hold the rails 10parallel to each other and a prescribed distance apart from each other.The prescribed distance between rails is very small, in the range offrom one-quarter inch (¼″) to 3 inches (3″), such as about 5/16 of aninch, one-half inch (½″), one inch (1″), or one and one-half inches(1½″). The rail clamps 12 comprise a clamp top 16 and clamp bottom 18joined by a screw 46, which can be an internal hex screw or any othersuitable screw. Rail clamp 12 can be made of any suitable material, suchas a metal such as stainless steel or aluminum, or it can be made of asuitable plastic. The pipes 10 can be made of any suitable material,such as a metal or plastic, such as aluminum or PAC, such as may befound in a hardware store. Pipes of a range of sizes can be used, suchas pipes with an outer diameter of between 1 and 3 inches, between 1½and 2½ inches, between 1½ and 2 inches, such as pipes with an outerdiameter of 1.5 inches, 1.66 inches, and 1⅞ inches.

Still referring to FIG. 1, a carriage plate 20 is mounted on the chassisassembly 24, described in detail below. The carriage plate 20 canfunction as an attachment interface for the attachment of a camera orcamera support such as a hi hat or camera head. Further, a flat mountingplate 22 can be mounted on the carriage plate and can also serve as aninterface between the dolly and camera or camera support. The flatmounting plate 22 may include on its surface an array of protectiverubber pads 26.

In an alternate embodiment, instead of the flat mounting plate 22, alevel able bowl interface can be mounted on the carriage plate 20. Thelevel able bowl interface can also serve as an interface between thedolly and camera or camera support.

Referring now to FIG. 2, in the embodiment shown, the skater 14comprises two chassis assemblies 24. Chassis assembly 24 comprises: atop wheel bracket 28, to which is attached a pair of large, fixed,urethane, load-bearing wheels 30; a side wheel bracket 32, which also isattached to the top wheel bracket 28; a pair of stabilizing wheels 36which are mounted on linearly adjustable brackets 34, which in turn aremounted on the side wheel bracket 32; and a carriage connection plateassembly 38. In this embodiment, the stabilizing wheels 36 are smallerthan, and perpendicular to, the urethane load-bearing wheels 30. Eachcarriage connection plate assembly 38 comprises a carriage connectionassembly top 40, a carriage connection assembly bottom 42, and carriageconnection assembly left and right sides 44 a and 44 b. In theembodiment illustrated, carriage connection assembly left and rightsides 44 a and 44 b are handed, that is, they are non-superposablemirror images of each other. In other embodiments, carriage connectionassembly left and right sides 44 a and 44 b may be identical to eachother and thus interchangeable with each other. The carriage plate 20attaches to and is parallel to the carriage connection assembly top 40.The carriage connection assembly sides 44 a and b feature an angled edgesuch that the carriage connection assembly bottom 42 is not parallel tothe carriage connection assembly top 40. The top wheel brackets 28 areattached to the carriage connection assembly bottom 42 of the carriageconnection assembly 38. Consequently, the top wheel bracket 28, and theload-bearing wheels 30 attached thereto, are angled at a fixed anglerelative to the carriage connection assembly top 40 and the carriageplate 20. This fixed angle can be set in the range of about 20 degreesto about 30 degrees. In the embodiment pictured, the fixed angle isabout 25 degrees. The angling of the load-bearing wheels permits them toroll past the clamp top 16.

Skater 14 components generally are made of suitable materials known andused in the art. In the skater 14 shown, the center-to-center distanceof the top wheels 30 is about 7¾ inches and the center-to-centerdistance of the stabilizing wheels is about 4.23 inches. The person ofordinary skill in the art can vary these distances as desired. Topwheels 30 in this embodiment have an outer diameter of about 2.58 inchesand the stabilizing wheels 36 have an outer diameter of about 0.75inches.

In some embodiments, the skater dolly can assume an orientation otherthan upright, such as sideways or upside-down or any orientation betweenupright and upside-down. Reference to “top” and “load-bearing” wheelsrefers to the wheels that are “to” and “load-bearing” when the skater isin upright position, even though, in other orientations, those wheelsare not necessarily top or load-bearing. Similarly, reference to “side”wheels refers to those wheels that are on the side when the skater is inupright position.

In certain of those embodiments of the invention that comprise a skater,the top wheels and side wheels are both made of urethane. In someembodiments, the side wheels are softer than the top wheels. Softer sidewheels help to eliminate any bumps caused by, for example,irregularities or unevenness in the rails. In other embodiments, such aswhen the skater is used in a sideways or upside-down position, such thatequipment mounted on the skater does not rest on top of the skater, theside wheels may be made of a harder urethane so that they possessgreater load-bearing capacity. In still other embodiments that comprisea skater, the side wheels and/or the top wheels can be made of rubber,plastic, metal, or other suitable material.

Referring now to FIG. 4, the exemplary embodiment shown illustrates theshort distance between the rails 10, which distance can be about 5/16 ofan inch, and also illustrates the angling of load-bearing wheels 30symmetrically away from vertical, permitting the wheels to roll pastclamp top 16.

Referring now to FIG. 5A, the exemplary embodiment shown illustrates theangling of load-bearing wheels 30, the perpendicularity of stabilizingwheels 36 to load-bearing wheels 30, the joining of clamp top 16 toclamp bottom 18 by clamp screw 46, and the points at which the clamp top16 and clamp bottom 18 contact rails 10. Clamp top 16 comprises twoangled lower surfaces, each of which makes contact with one rail 10.Bracket bottom 18 comprises two depressions, each of which supports onerail 10. In this embodiment, each depression is formed by three flatfaces angled substantially as shown in FIG. 5A, such that, as drawn, oneface is horizontal and the other two are angled up. In the exemplaryembodiment illustrated, the clamp top 16 is configured and positionedsuch that, when the clamp is tightened, it makes one contact with eachpipe 10, while the clamp bottom 18 is configured and positioned suchthat, when the clamp is tightened, it makes two contacts with each pipe10. Each pipe 10 touches two angled (non-horizontal) faces of clampbottom 18. In the exemplary embodiment illustrated, the prescribeddistance between the two rails is approximately 5/16 inches. In otherembodiments, the prescribed distance can be less than or greater than5/16 inches, such as in the range of from one-fourth (¼) to three (3)inches, such as, for example, 6, 7, 8, 9, 10, 11, or 12 sixteenths of aninch, or 1, 1¼, or 1½ inches. This distance may be selected by the user.Other dimensions may be varied proportionally, as necessary or desired,with the inter-rail distance. Clamp bottoms 18 of different widths canbe prepared to provide different prescribed distances between the rails.

Still referring to FIG. 5A, the exemplary embodiment shown illustratesthe ease of assembly of this embodiment of the inventive system. Thepipes are positioned between the clamp top 16 and clamp bottom 18 andclamp screw 46 is tightened, thus pressing the top and bottom platesagainst the pipes 10 and securing the pipes in the clamp. The clamp thuscan offer the advantage over the prior art of simple assembly with asingle screw to achieve secure positioning of the pipes 10.

Still referring to FIG. 5A, in the exemplary embodiment shown, the outerdiameter of each rail 10 is 1.66 inches. Such pipes are an ANSI/SAMEstandard size. They may typically be referred to as “1¼ Nominal PipeSize” at a retail outlet such as a hardware store or metal supplier. Theremaining structures are drawn to scale relative to the rails. Allangles are substantially as shown. The system is salable to differentsizes. In the exemplary embodiment shown, the center-to-center distancefor pipes 10 is 2 inches. This distance can be varied, for example itmay be increased, in accordance with the user's preference, by, forexample, widening the central portion of clamp bottom 18 and adjustingother dimensions accordingly, while maintaining the pipe size, forexample.

Still referring to FIG. 5A, in the exemplary embodiment shown, theleft-to-right width of clamp bottom 18 may be about 3 to about 5 inches,for example about 4 inches, preferably 3.95 inches, and thefront-to-back depth can be about 1.5 to about 4 inches, such as fromabout 2 to about 3 inches, for example, preferably 2.0 inches. In apreferred embodiment, the clamp bottom 18 can have the following furthermeasurements: first, noting that clamp bottom 18's right and left halfare symmetrical with each other; considering the top surface, there arethree horizontal surfaces, one in the center and two on either side. Ina preferred embodiment: the center horizontal surface is about 0.455inches in length, the right and left horizontal surfaces are about 0.633inches in length, the height of the center horizontal surface above theleft and right horizontal surfaces is about 0.531 inches, the angle madeby the left or right horizontal surface and the corresponding (inner)angled face that joins each to the center horizontal face is 125 degrees

Referring now to FIG. 5B, in the exemplary embodiment shown, it can beseen that, by virtue of the positioning and orientation of thestabilizing wheels 36 relative to the load-bearing wheels 30, the skater14 remains secured to the rails 10 when the skater, rail and clampsystem 1 is rotated 90 degrees from horizontal.

Referring now to FIG. 5C, in the exemplary embodiment shown, it can beseen that, by virtue of the perpendicularity of the stabilizing wheels36 to the load-bearing wheels 30, the skater 14 remains secured to therails 10 when the skater, rail and clamp system 1 is rotated 180 degreesfrom horizontal. A camera mounted on system 1 thus can be rotated awayfrom a horizontal orientation while continuing to run smoothly along therails 10 of the inventive system 1. For example, the inventive system 1may be rotated about an axis that runs parallel to the rails 10 while acamera mounted on skater 14 runs along the rails.

Referring now to FIG. 6, the exemplary embodiment shown is substantiallythe same as the embodiment shown in FIG. 1 except the exemplaryembodiment of the system 2 shown in FIG. 6 further comprises a motorassembly 60 mounted on the skater 14 and a belt 62 running the length ofthe rails, along which the motor assembly 60 pulls the skater 14. Thebelt 62 is secured in place by belt clamps 64, which comprise an outerpiece belt clamp bottom 68 and inner piece belt clamp top 70. Motorpulley system 76 comprises the motor assembly 60, the belt 62, idlerpulleys 78, and motor adapter plate 80.

Referring now to FIG. 7, the exemplary embodiment of system 2 is thesame as that of FIG. 6. Belt holder adapter plate 66 is mounted on andjoined to clamp top 16. Belt clamp 64 comprises outer piece belt clampbottom 68 and inner piece belt clamp top 70. Belt 62 fits vertically inbelt clamp opening 72. Tightening of wing nut 74 forces belt clamp top70 down along the inclined face of belt clamp bottom 68, thus causingbelt clamp top 70 also to move laterally, narrowing opening 72 andsecuring the belt 62 vertically between the inside vertical face of beltclamp bottom 68 and the outer vertical face of belt clamp top 70. Motorpulley system 76 comprises the motor assembly 60, the belt 62, idlerpulleys 78, and motor adapter plate 80. The motor assembly 60 is securedto motor adapter plate 80, which is mounted to the underside of carriageplate 20.

The idler pulleys 78 are affixed to the motor adapter plate 80 by onescrew each. In the exemplary embodiment shown, a low friction bushing isused so that the idler pulleys 78 rotate freely. In other embodiments, aball bearing, for example, could be used in place of a bushing. Themotor assembly 60 provides the motive force that propels the skater 14along the belt 62.

The motor assembly 60 in this embodiment comprises a motor housing, amotor with drive electronics, electronic connectors for interfacing todrive electronics, a drive train consisting of a multistage gearreduction, and an output timing belt pulley.

Turning now to FIG. 10, the exemplary motorized embodiment of system 2is the same as that of FIG. 6. The embodiment as illustrated shows thatit provides a stopping point for the motorized skater 14. It can be seenthat the load-bearing wheels 30 cannot pass belt holder adapter plate 66and belt clamp 64. Consequently, skater 14 cannot roll off the end ofrails 10 during motorized movement.

Referring now to FIG. 11, the exemplary embodiment of system 3 asillustrated comprises two rails 10 held next to and parallel to eachother by rail clamp 12, comprising clamp top 16 and clamp bottom 18joined by the tightening of screw 46.

Turning now to FIG. 12, the exemplary embodiment of system 3 shown isthe same as that shown in FIG. 11 and substantially the same as thatshown in FIG. 5A except that the embodiment of FIG. 11 does not includea skater. All angles of this embodiment are substantially as shown. Thesystem is salable to different sizes.

Turning now to FIG. 13, the exemplary embodiment shown illustrates thatrail clamp 12 can join pipes 10 a and 10 b end-to-end while at the sametime securing pipes 10 a and 10 a side-by-side and pipes 10 b and 10 bside-by-side.

In any embodiment of any of systems 1, 2, and 3 that comprises more thanone rail clamp, it is preferred that all of the rail clamps are a railclamp 10 as described and illustrated herein, or an obvious variationthereon.

The person of ordinary skill in the art will be able to make obviousvariations of the invention described herein and the embodiments of theinvention described herein by applying no more than an ordinary level ofskill. Such variations are considered within the scope of the claimedinvention.

What is claimed is:
 1. A track system on which a skater dolly can roll,comprising: one or more pairs of side-by-side rails, and one or morerail clamps, wherein: at least one rail clamp comprises a clamp top, aclamp bottom and a clamp screw that joins the clamp top to the clampbottom, and further wherein said at least one rail clamp secures inplace at least one pair of side-by-side rails, and holds each member ofeach secured pair parallel to the other member of the pair, the distancebetween rails is between about 5/16 inches and about 3 inches, the clamptop comprises two angled lower surfaces, each of which makes contactwith one of the rails, and the clamp bottom comprises two depressions,each of which supports one rail, the track system further comprising askater dolly, wherein the skater dolly comprises a set of fourload-bearing wheels and a set of four stabilizing wheels, wherein theload-bearing wheels are angled 20-30 degrees away from vertical and thestabilizing wheels are approximately perpendicular to the load-bearingwheels, and further wherein the skater dolly can roll along the rails ofthe track system.
 2. The track system of claim 1, in which eachdepression of the clamp bottom is formed by three flat faces angled suchthat one face is horizontal and the other two are non-horizontal, andeach non-horizontal face makes contact with the rail that thecorresponding depression supports while the horizontal face does notmake such contact.
 3. The track system of claim 2, wherein the distancebetween rails is about 5/16 inches.
 4. The track system of claim 3,further comprising a motor pulley system that moves the skater along therails, wherein the motor pulley system comprises a motor assemblymounted on the skater, a belt, and idler pulleys.
 5. The track system ofclaim 3, wherein the load-bearing wheels are angled about 25 degreesaway from vertical.
 6. The track system of claim 4, wherein theload-bearing wheels are angled about 25 degrees away from vertical. 7.The track system of claim 2, comprising at least two pairs ofside-by-side rails, wherein at least one rail clamp secures two pairs ofrails end-to-end, such that end-to-end rails are aligned with each otherand side-by-side rails are parallel to each other.